Learning Targets
- I can find a unit rate by dividing the total by the number of units.
- I can identify and build equivalent ratios by multiplying or dividing both terms by the same number.
- I can find a percent of a number using ratio reasoning or multiplication.
- I can use rate reasoning to convert between quantities (e.g., miles per liter).
Teacher Notes (not printed)
Pacing
- Whole-class launch (5 min): Read the scenario aloud. Ask: "What does 'unit rate' mean in real life?"
- Independent work (20–25 min): Students work through Tasks 1–6. Circulate and prompt with Socratic questions.
- Debrief (5–10 min): Share Part 3 (equivalent ratios) and Part 5 (percent) on the board. Discuss strategies.
Grouping Suggestions
- Partners: Pair students for Tasks 3–4 (ratio tasks) to encourage discourse.
- Individual: Tasks 1, 2, 5, 6 for independent practice and accountability.
Differentiation — Support
- Provide a ratio table graphic organizer for Tasks 3–4.
- Allow calculator use on Tasks 5–6 for students with IEP/504 accommodations.
- Pre-teach vocabulary: ratio, rate, unit rate, percent, equivalent.
Differentiation — Challenge
- Ask: "Could you write Task 6 as a proportion and solve it? Show two methods."
- Have students create a second equivalent ratio for Task 3 that was NOT listed as an answer.
- Extension: find what percent of the 80-liter tank is filled after 30 liters are used.
ESOL / Language Supports
- Pair the word "rate" with a visual (price tag per item, speedometer).
- Post a bilingual vocabulary card: rate / tasa, ratio / razón, percent / por ciento.
- Allow oral responses or drawing for the reflection prompt.
Pit-Crew Architect — Build the Winning Race Car
What to do: You are the pit-crew engineer in Ratio Rally. Build each car part by setting rates, ratios, and percents. Tap, drag, or set the numbers, then press Check My Build.
Tune the Fuel Price (unit rate)
4 cans of fuel cost $12. Set the price for 1 can.
Hint: $12 ÷ 4 cans = price for 1 can.
Set the Engine Speed (miles per hour)
The car goes 150 miles in 3 hours. Type the speed for 1 hour.
Hint: 150 miles ÷ 3 hours = miles in 1 hour.
Match the Tire Mix (equivalent ratio)
The grip mix is 2 red : 3 blue. Tap the lane with the same ratio.
Hint: multiply both numbers by the same amount. 2×3 and 3×3.
Scale Up the Pit Crew (equivalent ratio)
1 driver needs 5 helpers. Build the crew for 4 drivers. Set the number of helpers.
Hint: 4 drivers is 4 times 1 driver, so multiply helpers by 4.
Charge the Boost Bar (percent of a number)
The full tank holds 80 liters. Fill the bar to 25% of the tank. Then type how many liters that is.
Hint: 25% means 25 out of 100. 25% of 80 = 80 ÷ 4.
Measure the Track (convert units)
The car uses 2 liters of fuel for every 10 miles. Type how many miles it can go on 6 liters.
Hint: 2 liters = 10 miles, so 1 liter = 5 miles. Then ×6.
Scoring Rubric
| Level | Score | Description |
|---|---|---|
| 4 — Exceeds | 6 / 6 | All 6 parts correct. Demonstrates fluent unit-rate, equivalent-ratio, and percent reasoning. Work is complete and precise (e.g., slider set to exactly 25%, correct equivalent ratio identified on first try). |
| 3 — Meets | 4–5 / 6 | Most rate and ratio tasks correct; may have one arithmetic slip on the percent or fuel-conversion task. Equivalent-ratio logic is clearly applied. |
| 2 — Approaching | 2–3 / 6 | Some correct unit rates or ratios, but errors indicate partial understanding (e.g., adds instead of multiplies for equivalent ratios, or confuses percent with the whole number). |
| 1 — Beginning | 0–1 / 6 | Attempts made but answers reflect significant misunderstanding of rate/ratio/percent concepts. Needs direct instruction and guided practice before re-attempt. |
Answer Key (not printed)
Part 1 — Fuel Price (Unit Rate)
Answer: $3 per can. Reasoning: $12 ÷ 4 cans = $3/can.
Part 2 — Engine Speed (Unit Rate)
Answer: 50 miles per hour. Reasoning: 150 miles ÷ 3 hours = 50 mph.
Part 3 — Tire Mix (Equivalent Ratio)
Answer: 6 : 9. Reasoning: 2 × 3 = 6 and 3 × 3 = 9. Both terms scaled by 3 → same ratio. Distractors: 2:5 (different sum), 4:9 (4÷2=2 but 9÷3=3, different scale factor), 3:2 (reversed).
Part 4 — Pit Crew (Equivalent Ratio)
Answer: 20 helpers. Reasoning: 1 driver : 5 helpers → 4 drivers : 4 × 5 = 20 helpers.
Part 5 — Boost Bar (Percent of a Number)
Answer: 20 liters. Reasoning: 25% of 80 = 80 × (25/100) = 80 × 0.25 = 20. Equivalently, 80 ÷ 4 = 20. Slider should be set to 25%.
Part 6 — Track Distance (Rate Reasoning)
Answer: 30 miles. Reasoning: Unit rate = 10 miles ÷ 2 liters = 5 miles/liter. Then 6 liters × 5 miles/liter = 30 miles.
Reflection
Deliverable: Enter your name in the field above, complete all 6 tasks, write your reflection, then press Check My Build to submit and save your score as a PDF or DOC.